Modified Sialic Acids on Mucus and Erythrocytes Inhibit Influenza A Virus Hemagglutinin and Neuraminidase Functions

Journal of Virology · April 16, 2020

Karen N. Barnard, Brynn K. Alford-Lawrence, David W. Buchholz, Brian R. Wasik, Justin R. LaClair, Hai Yu, Rebekah Honce, Stefan Ruhl, **Petar Pajic**, Erin K. Daugherity, Xi Chen, Stacey L. Schultz-Cherry, Hector C. Aguilar, Ajit Varki, Colin R. Parrish

Sialic acids (Sia) are the primary receptors for influenza viruses and are widely displayed on cell surfaces and in secreted mucus. This study examines how modified forms of Sia found on mucus and erythrocytes inhibit influenza A virus (IAV) hemagglutinin binding and neuraminidase activity.

The modifications of Sia in mucus may therefore have potent effects on the functions of IAV and may affect both pathogens and the normal flora of different mucosal sites, suggesting host sialic acid diversity itself acts as a layer of innate defense against influenza infection.

#mucins #genomics

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